<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Login Page</title>
    <style>
        body {
            font-family: Arial, sans-serif;
            background-color: #f4f4f9;
            display: flex;
            justify-content: center;
            align-items: center;
            height: 100vh;
            margin: 0;
        }
        .login-container {
            background-color: white;
            padding: 20px;
            border-radius: 10px;
            box-shadow: 0px 4px 6px rgba(0, 0, 0, 0.1);
            width: 300px;
        }
        h2 {
            text-align: center;
        }
        .input-field {
            width: 100%;
            padding: 10px;
            margin: 10px 0;
            border: 1px solid #ccc;
            border-radius: 5px;
        }
        .submit-btn {
            width: 100%;
            padding: 10px;
            background-color: #4CAF50;
            color: white;
            border: none;
            border-radius: 5px;
            cursor: pointer;
        }
        .submit-btn:hover {
            background-color: #45a049;
        }
        .error {
            color: red;
            font-size: 12px;
        }
    </style>
</head>
<body>

<div class="login-container">
    <h2>Login</h2>
    <form id="loginForm" onsubmit="return validateForm()">
        <div>
            <input type="text" id="username" class="input-field" placeholder="Username" required>
            <span id="usernameError" class="error"></span>
        </div>
        <div>
            <input type="password" id="password" class="input-field" placeholder="Password" required>
            <span id="passwordError" class="error"></span>
        </div>
        <button type="submit" class="submit-btn">Login</button>
    </form>
</div>

<script>
    function validateForm() {
        let username = document.getElementById("username").value;
        let password = document.getElementById("password").value;
        let usernameError = document.getElementById("usernameError");
        let passwordError = document.getElementById("passwordError");
        let valid = true;

        // Clear previous errors
        usernameError.textContent = "";
        passwordError.textContent = "";

        // Check if username is empty
        if (username === "") {
            usernameError.textContent = "Username is required.";
            valid = false;
        }

        // Check if password is empty
        if (password === "") {
            passwordError.textContent = "Password is required.";
            valid = false;
        }

        return valid;
    }
</script>

</body>
</html>
